A known armchair of this type, which Applicants are exploiting, comprises on each side of the seat and the backrest:
a crossed support, whose front and rear legs are joined to each other, in their substantially median part, by a pivot pin,
a seat, of which the front part is joined to the upper part of the rear leg by a pivot pin and of which the rear part is provided with a rack adapted to cooperate with a finger projecting from the upper part of the front leg,
a compass element of which the rear arm is mounted to pivot about a pivot pin joining the lower part of the backrest to the upper part of the front leg, which pin is located above the finger of the front leg cooperating with the rack of the seat, and of which the front arm is connected to the seat by a pivot pin located between the rack thereof and its pivot pin on the front leg,
an armrest, whose rear part is connected to an intermediate part of the backrest by a pivot pin and whose front part is provided with a rack adapted to cooperate with a finger projecting from the front arm of the compass element above the pivot pin of the two arms.
In this known armchair, the rear arm of each compass element is terminated by an elastically clippable hook so that, in position of use of the armchair, the hooks may pivot about the pivot pin of the backrest on the front leg during adjustment of the inclination of the backrest, the hooks having to be disengaged when the armchair is to be folded. Furthermore, the fingers of the compass elements are imprisoned in the racks of the armrests in a stroke limited to the pivoting of the backrest.
Consequently, it is relatively difficult to fold the armchair by oneself; as to unfolding, it requires a certain apprenticeship and perfect centering on both sides: in the notch selected out of the five notches of each lateral rack for adjusting the seat height and in the notch selected out of the four notches of each lateral rack for adjusting the inclination of the backrest.
This known armchair presents a second drawback resulting from its folding up by bringing the backrest onto the seat, straightening the crossed legs, disengagement of the hook on the rear arm of each compass element and flattening of each armrest on the front arm of the corresponding compass element. The armchair thus folded is difficult to store in a garden shed or sales store, since, due to its shape, it is unstable on its base and difficult to lean laterally against others. More important, from the economical standpoint, is that the storage volume in a vehicle for these folded armchairs contained in parallelepipedic cardboard packings is reduced: of the order of 5 to 6 armchairs per cubic meter. Consequently, transport costs are relatively high.
Another known armchair is marketed by Kettler. It comprises, like the preceding one:
a backrest and a seat mounted to pivot on each other,
a crossed support, of which the two legs, located on each side, are articulated with respect to one another and connected to the seat; however, the front leg is articulated on the rear part of the seat, whilst the rear leg comprises a projecting finger cooperating with a front lateral rack on the seat,
armrests articulated on the backrest and extending above the seat, each armrest being supported by an upright which, at the top, comprises a projecting finger cooperating with a front rack on the armrest in question and, at the bottom, is connected to the seat by a pivoting hub lockable for different inclinations with the aid of a lever.
This armchair is even more difficult than the preceding one to fold by oneself, as one would need three hands if not assisted. Furthermore, the mechanism of inclination and its lever are relatively fragile and, as they are subjected to intense stresses, they frequently break, rendering the use of the armchair dangerous.
More especially, this armchair which also folds down flat is difficult to store, the loading capacity of a vehicle is reduced, leading to relatively high transport costs.
A third known armchair is described in Italian Patent Application No. 5208 A/82. It resembles more the former and, in fact, comprises:
a backrest mounted to pivot on each side on a front leg which is articulated on a rear leg in order to constitute a crossed support,
a seat of which the front part is articulated on each side of the corresponding rear leg and of which the rear part presents on each side a rack cooperating with a projecting finger located at the top of the front leg,
armrests articulated on the backrest and extending above the seat, each armrest being supported by a compass element of which the two arms are articulated on each other at the top and connected by a finger to a front rack on the armrest in question,
a front compass arm having a constant length and a telescopic rear arm of which the two parts are connected to each other by a lock-pusher making it possible, when it is actuated, to vary the length of said arm when the armchair is being folded down.
This third known armchair has the same drawbacks as the second: impossibility for one person to fold the armchair easily, fragility of the two lateral locks risking rendering the use of this armchair dangerous, storage of the folded armchair difficult and limited loading capacity of the means of transport.
It is an object of the present invention to overcome the above-mentioned drawbacks of the known armchairs by rendering folding and storage thereof without packaging simple and easy, considerably improving its robustness and reducing the space requirement of the folded and packaged armchairs so that the storage capacity of the transport vehicles is substantially increased, proportionally reducing transport costs.